It is known in the beverage dispensing art to use cold plates to provide heat exchange cooling of drinks. The cold plate itself is cooled by a volume of ice placed in contact with it and, in turn, provides for cooling of beverage liquids flowed through circuits or tubes embedded in the cold plate. A cold plate often is used in conjunction with a post-mix beverage dispenser, in which case sources of plain and carbonated water and beverage syrup flavorings are connected to the cold plate to be cooled as they are passed through the cold plate circuits. A carbonated or non-carbonated drink is then produced when the cooled carbonated or plain water and syrup flavoring constituents are subsequently mixed together and dispensed from a post mix valve.
To provide carbonated water for beverages, a carbonator tank serves as a source of carbonated water and usually is located within the beverage dispenser housing for producing carbonated water through mixture of plain water and carbon dioxide gas. Associated with the carbonator tank are a carbonator pump for delivering potable plain water into the tank and a source of CO2 gas for introduction into the tank for mixture with the potable water in the tank to provide carbonated water, all in a manner well-known in the art. To maintain sufficient water in the carbonator tank for proper carbonation and to meet demands for carbonated water in the serving of beverages, a liquid level sensor customarily is located inside of the tank for sensing the level of water in the tank and for controlling operation of the carbonator pump to deliver water to the tank, as required, to maintain an adequate level of water in the tank. To ensure that the carbonator tank does not become internally overpressurized, a self-actuating pressure relief safety valve is provided on the tank to automatically vent pressure from the tank upon occurrence of an overpressure condition.
A problem with beverage dispensers that use carbonators concerns placement of the carbonator within the dispenser. Locating the carbonator to the exterior of a dispenser is known, but ambient warming of the carbonator and its contents then becomes a problem in terms of dispenser performance and increased ice usage, since the cold plate is then required to chill carbonated water that is warmer than would be the case if the carbonator were located within the dispenser. It therefore is more common and desirable to locate the carbonator in the interior of the beverage dispenser housing, advantageously in a location where heat exchange cooling of the carbonator tank occurs to chill the carbonated water. However, a difficulty that arises is in choosing the particular location for the carbonator, since the liquid level sensor inside of the carbonator tank and the pressure relief safety valve on the tank are serviceable parts that can and do malfunction and require periodic replacement. If the carbonator is placed in a relatively inaccessible location within the dispenser housing, should the liquid level sensor and/or pressure relief safety valve fail or require periodic replacement or maintenance, considerable disassembly of the beverage dispenser, at considerable cost, can be required to access and service the carbonator for repair or replacement of its components. Unfortunately, as ice/beverage dispensers evolve to offer more and more features and performance advantages to users, the space available inside of dispenser housings for convenient and accessible mounting of carbonators has become ever more scarce, often leaving no choice but to mount the carbonator within the dispenser housing at a location that makes it relatively inaccessible and difficult to reach for service or repair of its liquid level sensor and pressure relief valve.
Accordingly, it would be very desirable to have the serviceable parts of a carbonator positioned at a relatively easily accessible location within a beverage dispenser housing, even though the carbonator tank itself may of necessity be positioned at a relatively inaccessible location.